Molecularly imprinted SPE and MEKC with in-capillary sample preconcentration for the determination of digoxin in human urine.

Molecularly imprinted solid-phase extraction (MISPE) combined with MEKC was used for clean-up, preconcentration and determination of digoxin in the presence of its aglycon digoxin (digoxigenin) in human urine samples. In addition, the use of an in-capillary sample concentration electrophoretic techn...

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Detalles Bibliográficos
Autores: Guijarro Díez, Miguel, Crego Navazo Antonio L., Marina Alegre, María Luisa, Paniagua González, Gema, Fernández Hernando, Pilar
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Universidad Nacional de Educación a Distancia
Repositorio:e-spacio. Repositorio Institucional de la UNED
Idioma:inglés
OAI Identifier:oai:e-spacio.uned.es:20.500.14468/11605
Acceso en línea:https://hdl.handle.net/20.500.14468/11605
Access Level:acceso abierto
Palabra clave:Digoxin
In-capillary sample preconcentration
Micellar electrokinetic chromatography
Molecularly imprinted solid-phase extraction
Sweeping
Descripción
Sumario:Molecularly imprinted solid-phase extraction (MISPE) combined with MEKC was used for clean-up, preconcentration and determination of digoxin in the presence of its aglycon digoxin (digoxigenin) in human urine samples. In addition, the use of an in-capillary sample concentration electrophoretic technique by sweeping was investigated to enhance the concentration sensitivity in MEKC. The highly selective, fast and effective sample pretreatment by MISPE along with the preconcentration by sweeping could overcome the low sensitivity of the highly efficient capillary electrophoresis separation with UV detection. The optimization of the variables affecting the separation as well as MISPE conditions procedure was carried out to select the best conditions of selectivity and sensitivity to determine digoxin at low concentration levels in urine. To demonstrate the suitability of the developed method several analytical characteristics (selectivity, linearity, accuracy, precision, and LOD) were evaluated. Satisfactory results were obtained in terms of linearity (r > 0.99), recovery (95.4–96.5% with RSD from 1.3% to 2.6%), precision (RSD from 0.3% to 1.7% for migration times and from 2.1% to 7.3% for corrected peak areas), and sensitivity (LODs of 6 μg/L with 5 mL of sample or 1.2 μg/L with 25 mL). The proposed MISPE-MEKC method was satisfactorily applied to the analysis of spiked human urine samples achieving a concentration factor up to 7500-fold.